The orbital-motion tag has no wiki summary.
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How does a spacecraft's orientation get determined
What method are employed to determine a spacecraft orientation with respect to a known orientation or plane?
Are gyroscopes reliable enough to make this determination, for example in Voyager ...
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1answer
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What tools do I need to track an orbit of a mystery object?
A while back I was observing Uranus with my 6" dob and a moving object tracked across my field of view. I was at about 90x at the time, and the object was pretty bright but slow moving. I dropped down ...
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1answer
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What are the temperatures of objects in Low Earth Orbit (LEO)?
What is the temperature of objects in Low Earth Orbit?
Consider LEO to be 600km to 800km.
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Calculation of a Gravity Resonance Keyhole
Can anyone describe the mathematics behind the calculation of a resonance keyhole (for a two-body model)? It seems like the size and position of the keyhole should be a function only of mass and ...
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Why all rocks are not orbiting bigger rocks in space?
Why only big rocks (planets) have satellites and not small ones? Why cosmic dust doesn't orbit rocks that are many times heavier than the dust grains? If dust is still too heavy then what about ...
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Are orbiting planets an example of perpetual motion?
I understand that perpetual motion is impossible, but I became confused when a friend of mine told me that the orbits of the planets is an example of perpetual motion. Will earth's orbit ever end, and ...
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2answers
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Is it possible to orbit the sun next to Earth?
With Geostationary orbit your limited to the equator and ~36000km.
Would it be possible to orbit the sun at the same speed as Earth, and then in basically the same place so that the distance to the ...
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4answers
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Does mass affect speed of orbit at a certain distance?
Does the mass of both the parent object, and the child object affect the speed at which the child object orbits the parent object?
I though it didn't (something like T^2 = R^3) until I saw an planet ...
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The feasibility of a satellite orbiting at a fixed time
I was speaking with some friends of mine, one of whom was an aerospace engineer. He posited the infeasibility of a hypothetical "Margaritaville Satellite" that orbited earth in such a way that ...
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Are there planetary systems where the planes of orbits vary greatly?
Inspired by this question, are there any known planetary systems with largely varying planes of orbit? For example a system where two planets have perpendicular planes?
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Questions about the Solar System
Most images you see of the solar system are 2D and all planets orbit in the same plane. In a 3D view, are really all planets orbiting in similar planes? Is there a reason for this? I'd expect that ...
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Measuring acceleration of earth due to its fall around the sun
Every orbiting of a satellite around a mass is nothing else but a constant fall - and therefore acceleration - towards this mass. In a way it is a "falling around" that mass.
My question Is it ...
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1answer
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Find true anomaly given period, eccentricity and time
Is it possible to find the true anomaly of an object in a Kepler orbit given the orbital period of the object, the orbital eccentricity and the time? Assuming a two body system and the mass of the ...
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Why are Saturn's rings so thin?
Take a look at this picture (from APOD http://apod.nasa.gov/apod/ap110308.html):
I presume that rocks within rings smash each other. Below the picture there is a note which says that Saturn's rings ...
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4answers
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Are tidal power plants slowing down Earth's rotation?
Are tidal power plants slowing down Earth's rotation to the speed of the orbiting moon? (1 rotation per 28 cca days)
Are they vice versa increasing the speed of moon orbiting by generating some ...
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3answers
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Missing something basic about simple orbital mechanics
I seem to be missing something basic.
I've been trying to get a simple orbital simulation working, and my two objects are Earth around the Sun.
My problem is this. I placed the Earth at 93M miles ...
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3answers
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How is it possible for orbits to maintain stability?
According to $a = v^2/R$, the circular velocity and radial distance between two attracting objects (such as planets), must remain in perfect proportion in order for orbital motion to take place. How ...
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Why an object travels a circular path?
It might sound stupid but seriously I couldn't find why?
We have a mass with a constant speed, which is acted on by a unit force which is always at right angles to its direction of motion.
Why do ...
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How does electron excitation relate to atomic orbitals?
Taking off from the Rutherford-Bohr model,
Figure 1. Rutherford-Bohr model.
when an electron absorbs energy (from light, heat, or otherwise) it jumps to a higher energy level, or shell. Then when ...
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Why GPS is at LEO?
Why GPS/GLONASS/Galileo satellites are on low earth orbit?
Why geostationary orbit is so bad? Sattelites might be placed there 'statically' and more precise...
The only problem I can see is ...
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How accurately is the moment of perihelion of Earth known, and how is it measured?
Earth's perihelion passed about nine hours ago. How accurately do we know the moment of closest approach of the Earth to the center of the sun? How do we make this measurement?
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Why are the orbits of planets in the Solar System nearly circular?
Except for Mercury, the planets in the Solar System have very small eccentricities.
Is this property special to the Solar System? Wikipedia states:
Most exoplanets with orbital periods of 20 ...
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Orbital mechanics of Dragon's Egg
In the novel Dragon's Egg, the human crew use one asteroid to swing other asteroids in place to counter the gravity of the neutron star. I understood that it was similar to a gravity sling shot, but I ...
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Is there a conserved quantity that enforces planar orbits in central force motion?
From what I remember, one of the first steps in finding the equations of motion for an orbiting body is to argue that the body's motion has to be restricted to a plane, because the central force has ...
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How to calculate a ballistic trajectory for a suborbital flight?
I'm trying to calculate the initial launch angles and velocity of a projectile (atmosphere's effects can be neglected), assuming that I know the lat/lon coordinates of both the launch and the ...
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Is the distance between the sun and the earth increasing?
M = mass of the sun
m = mass of the earth
r = distance between the earth and the sun
The sun is converting mass into energy by nuclear fusion.
$F = \frac{GMm}{r^2} = \frac{mv^2}{r} \rightarrow r ...
